From 19b2edb0f4484f173e8ebf8f7028cd844e4f1b33 Mon Sep 17 00:00:00 2001
From: dbr <dbr.onix@gmail.com>
Date: Sun, 1 Aug 2021 12:38:37 +1000
Subject: [PATCH 1/3] Add example of using list clipper API

Somewhat relates to #438
---
 imgui-examples/examples/long_list.rs | 33 ++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 imgui-examples/examples/long_list.rs

diff --git a/imgui-examples/examples/long_list.rs b/imgui-examples/examples/long_list.rs
new file mode 100644
index 0000000..ffa4dba
--- /dev/null
+++ b/imgui-examples/examples/long_list.rs
@@ -0,0 +1,33 @@
+/// Demonstrates using the "list clipper" to efficiently display long
+/// lists in a scrolling area.
+///
+/// You specify the height per item, and the `ListClipper` API will
+/// provide which item index are visible. This avoids having to create
+/// thousands of items only for them to not be made visible.
+///
+/// Note this requires a fixed (or easily computable) height per item.
+use imgui::*;
+
+mod support;
+
+fn main() {
+    let lots_of_words: Vec<String> = (0..10000)
+        .map(|x| format!("Line {}", x).into())
+        .collect();
+
+    let system = support::init(file!());
+    system.main_loop(move |_, ui| {
+        Window::new(im_str!("Hello long world"))
+            .size([300.0, 110.0], Condition::FirstUseEver)
+            .build(ui, || {
+                let mut clipper = imgui::ListClipper::new(lots_of_words.len() as i32)
+                    .items_height(ui.current_font_size())
+                    .begin(ui);
+                while clipper.step() {
+                    for row_num in clipper.display_start()..clipper.display_end() {
+                        ui.text(&lots_of_words[row_num as usize]);
+                    }
+                }
+            });
+    });
+}

From 15c28266907517051d234b19cbec5d8926aae3e0 Mon Sep 17 00:00:00 2001
From: dbr <dbr.onix@gmail.com>
Date: Sat, 4 Sep 2021 12:21:00 +1000
Subject: [PATCH 2/3] Fix fmt

---
 imgui-examples/examples/long_list.rs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/imgui-examples/examples/long_list.rs b/imgui-examples/examples/long_list.rs
index ffa4dba..62791cf 100644
--- a/imgui-examples/examples/long_list.rs
+++ b/imgui-examples/examples/long_list.rs
@@ -11,9 +11,7 @@ use imgui::*;
 mod support;
 
 fn main() {
-    let lots_of_words: Vec<String> = (0..10000)
-        .map(|x| format!("Line {}", x).into())
-        .collect();
+    let lots_of_words: Vec<String> = (0..10000).map(|x| format!("Line {}", x).into()).collect();
 
     let system = support::init(file!());
     system.main_loop(move |_, ui| {

From d7470caa4c6e94d9d9ed3b7a80407d1b818c2eaf Mon Sep 17 00:00:00 2001
From: Jack Spira <jjspira@gmail.com>
Date: Sun, 5 Sep 2021 12:12:00 -0700
Subject: [PATCH 3/3] rebased and minor clippy fix

---
 imgui-examples/examples/long_list.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/imgui-examples/examples/long_list.rs b/imgui-examples/examples/long_list.rs
index 62791cf..79278af 100644
--- a/imgui-examples/examples/long_list.rs
+++ b/imgui-examples/examples/long_list.rs
@@ -11,7 +11,7 @@ use imgui::*;
 mod support;
 
 fn main() {
-    let lots_of_words: Vec<String> = (0..10000).map(|x| format!("Line {}", x).into()).collect();
+    let lots_of_words: Vec<String> = (0..10000).map(|x| format!("Line {}", x)).collect();
 
     let system = support::init(file!());
     system.main_loop(move |_, ui| {